Sending messages – Rockwell Automation 5720 DriveLogix System User Manual
Page 157
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Publication 20D-UM002C-EN-P - November 2003
Communicating with Devices on a ControlNet Link 7-11
Sending Messages
The DriveLogix controller can send MSG instructions to other controllers
over a ControlNet link. Each MSG instruction requires you to specify a target
and an address within the target. The number of messages that a device can
support depends on the type of message and the type of device:
MSG instructions are unscheduled. The type of MSG determines whether or
not it requires a connection. If the MSG instruction requires a connection, it
opens the needed connection when it is executed. You can configure the MSG
instruction to keep the connection open (cache) or to close it after sending the
message.
This device:
Support this many
unconnected messages:
Support this many
connected messages:
1756-CNB or 1756-CNBR module
(for a Logix5550 controller)
20
64
1788-CNx daughtercard
(for a DriveLogix controller)
5
32
with a maximum of 9 scheduled
ControlNet PLC-5 controller
32
128
This type of message:
And this communication method:
Uses a connection:
CIP data table read or write
X
PLC2, PLC3, PLC5, or SLC (all types)
CIP
CIP with Source ID
DH+
X
CIP generic
CIP
Optional
(1)
block-transfer read or write
X
(1)
You can connect CIP generic messages, but for most applications, we recommend you leave CIP generic messages unconnected.